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Öğe Effect of high hydrostatic pressure on seed germination, microbial quality, anatomy-morphology and physiological characteristics of garden cress (Lepidium sativum) seedlings(TAYLOR & FRANCIS LTD, 2013) Islek, Cemil; Altuner, Ergin Murat; Ceter, Talip; Alpas, HamiHigh hydrostatic pressure is a non-thermal food processing technology that is found to increase the percentage of germination, decrease the germination time and improve the microbial quality of seeds. In this study, pressures of 100-400MPa for 10min at 30 degrees C are used to compare the percentage of germination, the microbial quality of seeds, chlorophyll a and b, and total phenolic compounds concentrations in seedlings, and the anatomy-morphology characteristics of garden cress. Enhanced reductions of total aerobic mesophilic bacteria, total and fecal coliforms, and yeast and mould populations in seeds were observed, especially at 300MPa. In addition, the percentage of germination, chlorophyll content and phenolic compounds concentrations, fresh and dry weights, and hypocotyl lengths of the seedlings are higher than those of all samples, where the percentage of germination is equal to controls but higher than other samples, and radicula length is lower than controls but higher than others.Öğe Evaluation of the Effect of Different Extraction Techniques on Sour Cherry Pomace Phenolic Content and Antioxidant Activity and Determination of Phenolic Compounds by FTIR and HPLC(Springer, 2019) Okur, Ilhami; Baltacioglu, Cem; Agcam, Erdal; Baltacioglu, Hande; Alpas, HamiSour cherry pomace derived from mashed cherries that maintains the color and beneficial properties of the cherries (Prunus cerasus L.). In this study, microwave-assisted extraction (MAE) (900 W for 30, 60 and 90 s.), high hydrostatic pressure (HHP) (400 and 500 MPa for 1, 5 and 10 min at 20 degrees C) and ultrasonic-assisted extraction (UAE) (for 5,10 and 15 min with a power of 100%) was used as novel processes. Total phenolic content (TPC), morphological changes, antioxidant activity (AA) and structural changes of cherry pomace were measured by the Folin-Ciocalteu assay, high performance liquid chromatography (HPLC), DPPH-scavenging activity, scanning electron microscopy (SEM) and Fourier transform infrared spectrometry (FTIR). According to the results, all novel technologies (MAE-HHP-UAE) increase PC and AA with respect to conventional solvent extraction method (50 degrees C and 30 min) (CSE). Among novel technologies, MAE (90 s) had highest TPC (275.31 +/- 4.26 GAE/100 g FW) and also had highest antioxidant activity (89.9 +/- 0.22%). The lowest TPC and AA values were 108.36 +/- 3.99 mg gallic acid equivalent (GAE)/100 g fresh weight (FW) and 71.30 +/- 1.21% in CSE, respectively. According to FTIR results, there are no significant structural changes in samples when different extraction techniques were applied. Individual phenolics were quantified by using HPLC for different extraction techniques. GraphicÖğe High hydrostatic pressure assisted extraction of pectin from sugar beet pulp(Wiley, 2021) Kaya, Burcu; Okur, Ilhami; Alpas, Hami; Oztop, Mecit HalilThis study aimed to investigate the effect of high hydrostatic pressure assisted extraction (HHPE) (250, 350 and 450 MPa at 40 degrees C for 5 min with/without acid addition) of pectin from sugar beet pulp and compare its properties with pectin obtained from conventional extraction (CE). Degree of esterification (DE), galacturonic acid (Gal-A) content, Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) relaxometry experiments were performed on the obtained pectin powder. HHPE (12.23 +/- 0.13%) doubled extraction yield compared to CE (6.43 +/- 0.07%). Also, HHPE and acid addition were found to have a synergetic effect on the extraction. HHPE resulted in degradations in the polymer structure and reduced Gal-A content and DE. Pectin extracted with both methods was classified as low methoxyl pectin (LMP). According to the NMR Relaxometry results, HHPE decreased water holding capacity (WHC). In brief, HHP was shown to increase the pectin extraction yield and no changes in viscosity were observed at the concentrations studied (2 g/L).Öğe Improving the physical properties of fish gelatin by high hydrostatic pressure (HHP) and ultrasonication (US)(Wiley, 2020) Sezer, Purlen; Okur, Ilhami; Oztop, Mecit Halil; Alpas, HamiIn this study, it was aimed to improve the physical properties of fish gelatin by using high hydrostatic pressure (HHP) and ultrasonication (US). Gelatin solutions were exposed to different pressures and ultrasonication separately and gelled afterwards. The physicochemical measurements based on gel strength, turbidity and rheology experiments showed that HHP treatment on fish and bovine gelatin stabilized the gelatin network by organising the structure and reducing the free volume. Both processing methods (HHP and US) increased the gel strength significantly (P < 0.05) compared with non-treated samples. Fourier-transform infrared spectroscopy (FTIR) results indicated that conformations of amino acids changed after the treatments. Furthermore, US treatment was shown to destroy the gelatin network, change the gelation mechanism and decreased the degree of aggregation. Both treatments improved the gel characteristics as gel strength, gelling and melting temperatures of the fish gelatin. At the end, the best combination for fish gelatin among HHP and US treatments was found as 400 MPa-10 degrees C-15 min pressurisation.Öğe Improving the Recovery of Phenolic Compounds from Spent Coffee Grounds (SCG) by Environmentally Friendly Extraction Techniques(Mdpi, 2021) Okur, Ilhami; Soyler, Betul; Sezer, Purlen; Oztop, Mecit Halil; Alpas, HamiThe aim of this study was to investigate and compare the effects of different extraction techniques (high hydrostatic pressure-assisted extraction (HHPE), ultrasound-assisted extraction (UAE), and classical solvent extraction (CSE)) on phenolic compounds from spent coffee grounds (SCG). Different HHPE parameters (300, 400 and 500 MPa at 25 degrees C for 5, 10 and 15 min) and UAE parameters (40%, 50%, and 60% amplitude at 25 degrees C for 5, 10 and 15 min) were used. These techniques were compared with CSE (at 50 degrees C for 30 min) according to total phenolic content (TPC), antioxidant activity (AA), high-performance liquid chromatography (HPLC), scanning electron microscopy (SEM), and infrared (IR) spectroscopy. The results showed that eco-friendly techniques increased the TPC and AA compared to CSE and morphological changes were verified by SEM results. Furthermore, chlorogenic and caffeic acid were also quantified by using HPLC. Chlorogenic acid was found as the main phenolic compound in spent coffee grounds (SCG). The highest chlorogenic acid was detected as 85.0 +/- 0.6 mg/kg FW with UAE at 60% amplitude for 15 min. In brief, for the extraction of phenolic compounds from waste SCG eco-friendly techniques such as HHPE and/or UAE were more convenient than CSE.Öğe Nuclear Magnetic Resonance (NMR) study of Palm Kernel Stearin: Effects of cooling rate on crystallization behaviour(Elsevier, 2022) Okur, Ilhami; Ozel, Baris; Ucbas, Derya; Grunin, Leonid; Okur, Purlen Sezer; Alpas, Hami; Ide, SemraIn this study, effects of different cooling rates (0.5,3.3,4.7 and 6.9 degrees C/min) on the crystallization behavior of palm-kernel-stearin (PKS) were studied by low-field NMR relaxometry. According to results, solid fat content (SFC), longitudinal relaxation time (T1), second moment (M2) and degree of crystallinity (%) of the samples increased with increase in cooling rate from 0.5 to 6.9 degrees C/min. In contrast, transverse relaxation time (T2) demonstrated an opposite behavior with respect to T1 and decreased when the cooling rate increased. Additionally, effects of cooling rate on the changes of polymorph structures were detected by X-ray measurements. Degree of crystallinity showed high Pearson correlation values (alpha <= 0.05) with SFC (r = 0.771) and T1(r = 0.932). Changes in the crystal polymorphs could also be explained by NMR parameters to some extent as can be observed by the strong correlation between the 13 crystal content and T2 (r = 0.927). At the highest cooling rate, 13 ' crystals were the dominant polymorphic form and constituted 75(%) of the total crystals present. Results of this study suggested that NMR relaxometry could be used as a complementary tool to interpret the crystallization behavior of PKS.Öğe Recent advances in gelatinisation and retrogradation of starch by high hydrostatic pressure(Wiley, 2021) Okur, Ilhami; Sezer, Purlen; Oztop, Mecit Halil; Alpas, HamiStarch is the major polysaccharide following cellulose, but native starch has limited application due to physicochemical and functional properties. To handle such problems, starch is usually modified with either thermal or more recently by non-thermal technologies such as high hydrostatic pressure (HHP). HHP is a non-thermal technique that can be applied to a variety of food materials with minimum effect on nutritional quality. High-pressure levels can cause physicochemical changes in starch such as partial/completely gelatinisation, reduction in solubility and swelling power, increasing pasting temperature and content of slowly digestible starch (SDS) and retention of retrogradation. These physicochemical changes depend on the starch type, pressurisation level, treatment time and temperature. This review has evaluated and synthesised the current research about the effect of HHP on starch gelatinisation, retrogradation and physicochemical properties of starch.Öğe Recovery of phenolic compounds from peach pomace using conventional solvent extraction and different emerging techniques(Wiley, 2024) Baltacioglu, Cem; Baltacioglu, Hande; Okur, Ilhami; Yetisen, Mehmet; Alpas, HamiThe study compared high-pressure, microwave, ultrasonic, and traditional extraction techniques. The following extraction conditions were implemented: microwave-assisted extraction (MAE) at 900 W power for durations of 30, 60, and 90 s; ultrasonic-assisted extraction (UAE) at 100% amplitude for periods of 5, 10, and 15 min; and high-pressure processing (HPP) at pressures of 400 and 500 MPa for durations of 1, 5, and 10 min. The highest yield in terms of total phenolic content (PC) was obtained in UAE with a value of 45.13 +/- 1.09 mg gallic acid equivalent (GAE)/100 g fresh weight (FW). The highest PC content was determined using HPP-500 MPa for 10 min, resulting in 40 mg GAE/100 g, and MAE for 90 s, yielding 34.40 mg GAE/100 g FW. The highest value of antioxidant activity (AA) was obtained by UAE in 51.9% +/- 0.71%. The PCs were identified through the utilization of Fourier transform infrared (FTIR) spectroscopy and high-performance liquid chromatography (HPLC). Utilizing multivariate analysis, the construction of chemometric models were executed to predict AA or total PC of the extracts, leveraging the information from IR spectra. The FTIR spectrum revealed bands associated with apigenin, and the application of HPP resulted in concentrations of 5.41 +/- 0.25 mg/100 g FW for apigenin and 1.30 +/- 0.15 mg/100 g FW for protocatechuic acid. Furthermore, HPLC analysis detected the presence of protocatechuic acid, caffeic acid, p-coumaric acid, and apigenin in both green extraction methods and the classical method. Apigenin emerged as the predominant phenolic compound in peach extracts. The highest concentrations of apigenin, p-coumaric acid, and protocatechuic acid were observed under HPP treatment, measuring 5.41 +/- 0.25, 0.21 +/- 0.04, and 1.30 +/- 0.15 mg/kg FW, respectively.Öğe The effect of high hydrostatic pressure on the physiological and biochemical properties of pepper (Capsicum annuum L.) seedlings(TAYLOR & FRANCIS LTD, 2015) Islek, Cemil; Altuner, Ergin Murat; Alpas, HamiHigh hydrostatic pressure is a non-thermal food processing technology, which also has several successful applications in different areas besides food processing. In this study, Capsicum annuum L. (pepper) seeds are subjected to 50, 100, 200 and 300MPa pressure for 5min at 25 degrees C and the seedlings of HHP processed seeds are used to compare percentage of seed germination and biochemical properties such as chlorophyll a, b and a/b, proline content, total protein, carotenoid, malondialdehyde, glucose, fructose and phenolic compounds concentrations. As a result of the study, it was observed that there are remarkable changes in terms of biochemical properties especially for seedlings, whose seeds were pressurized at 200 and 300MPa. More detailed studies are needed to put forward the mechanism behind the changes in biochemical properties.Öğe Triakontanol ve yüksek hidrostatik basıncın serbest ve tutuklanmış capsicum annuum L. hücre süspansiyon kültüründe kapsaisin üretimi üzerine etkisi(2015) İşlek, Cemil; Alpas, Hami; Koç, Esra; Altuner, Ergin Murat[Abstract Not Available]Öğe Using high hydrostatic pressure as an abiotic elicitor strategy for improving capsaicin production in free and immobilized cell suspension cultures of Capsicum annuum L.(Taylor & Francis Ltd, 2021) Islek, Cemil; Koc, Esra; Altuner, Ergin Murat; Alpas, HamiIn this study, the effects of immobilization and high hydrostatic pressure (HHP) on capsaicin production in cell suspension culture of pepper seeds at different application times were investigated. Callus cultures were obtained from in vitro germinated hypocotyl explants of pepper seedlings and cell suspensions were prepared from calluses. Immobilized cell suspension cultures with calcium alginate and free cell suspension cultures were obtained by using these cell suspensions. 50, 100, 200, 300 and 400 MPa were applied to both free and immobilized cell suspensions as an elicitor. When all the results were compared, the highest amount of capsaicin was achieved in immobilized cell suspensions on the tenth day as 293.187 mu g/g f.w at 400 MPa pressure. As a result, it can be concluded that the combined application of immobilization and elicitor (HHP) caused significant increases (p < .05) in the amount of capsaicin.
